I. Field of the Invention
This invention relates generally to power trowels for working newly poured concrete slabs and, more particularly, to an abrasive head for attachment to a power trowel having provision for quick removal and replacement of diamond abrasive slab contacting surfaces.
II. Discussion of the Prior Art
In preparing a concrete slab as a building floor, forms are set up and then wet concrete is poured into the area defined by the forms. While still in a flowable state, the concrete is screeded and floated to yield a generally level surface with the gravel submerged. Once the concrete begins to harden, it is troweled to remove irregularities such as pits and bumps that may be present to thereby yield a smooth finish. For larger areas, power trowels are commonly used. They are generally of two types, walk-behind and ride-on. These machines are relatively expensive. Often concrete floors in commercial buildings are later treated (after the concrete has cured) by polishing machines that drive abrasive floor-engaging pads to create a smooth, polished and attractive surface. The polishing machines are also relatively costly. It is therefore advantageous if the same machine used to perform the earlier troweling operation can subsequently be rapidly and inexpensively converted to permit it to be used in performing the concrete polishing operations.
When it is recognized that workers necessarily must change out the abrasive pads frequently to present variation in the grit size being utilized at different stages of the polishing operation where a coarse grit is initially used, nut graduating to finer grits depending on the ultimate appearance that is desired, it is desirable that one be able to perform the machine conversion and abrasive substitution procedure simply, quickly and easily.
It is accordingly a principle object of the present invention to provide an improved abrasive assembly for attachment to a power trowel and in which abrasive members can be rapidly and accurately replaced.